well i wouldnt know for sure but i had met a few blind people who could hear/smell things that we could hear and smell but not to any Nth degree like they could.

im sure there are adaptations to the human body's senses when parts get disabled etc but i wouldnt have a clue what extent that is.

Oh man, don't get me going on my sense of smell. Sometimes i wish i couldn't smell anything. It drives my wife crazy. She is very modest with scented things, but I notice every little detail. No joke, she started using listerine the other day, which is a strong scent I know, but I smelled it from the other end of the apartment (two rooms and a long hallway) and she got frustrated, because she can't so much as open a bottle of anything without me complaining "what's that smell?" haha. But it really stinks. I smell smoke anywhere and everywhere when it doesn't bother anyone else. I sometimes feel like i can't just get a break from smells. :-/ Heaven forbid the neighbors below us decide to cook their foreign wet diaper food ugh... lol

Quote:

Originally Posted by bigshot

It's been my experience that most true audiophiles are more familiar with how to pull out their credit card than they are familiar with what good sound is.

Seriously. It is crazy. I'm sort of the audiophile my audiophile friends used to look down upon for the things I'd buy like home depot speaker wire for less than $1 a foot. Yet they always thought my sound system was incredible. ha. They would buy the fancy speakers and i'd buy the ones i thought reproduced everything insanely well. My only problem is that i want my audio everywhere to be high quality. My car, my computer, my tv, my portable. Man that gets expensive... But I can't listen to mediocre sound!!! Unacceptable!!! hahaha

If anyones interested, the reason behind why blind people can hear better than most non-blind people has to do with brain plasticity. If the optical cortex receives no information (and there are varying types of blindness, including one where the information gets through but cannot be processed by anything but the amygdala, emotional centre of the brain, so the person cannot see but can still recognize if someone in front of him is happy or sad) then the nerve cells occupying that section of the brain cease to fire. If not used for a purpose, nerve cells will eventually be repurposed by another part of the brain, such as the auditory cortex. The nerve cells on the boundary of that used section of the brain will influence the unused nerve cells to fire with them until all unused nerve cells are being used again. There's a saying in Psychology to describe this, "Nerves that fire together, wire together".

There were experiments done a few decades ago on primates where nerves to a certain part of the body were severed from the brain. That part of the brain map in the primate initially showed up as blank but after a few months would start to light up again alongside nearby brain maps. They say we only use 10% of our brain. In context, this may be true but rest assured that every neuron in a healthy brain either has or will be given a purpose.

On the other hand, we're physically limited to hearing around 19 to 20kHz thanks to the hair follicles in our cochlea. There is no useful evolutionary function for humans to hear over 20kHz and if you can indeed hear supersonic sounds you would be in the very, very tiny minority of genetic mutations. Of course, people who hear over 20kHz do exist but whether its a quarter of all head-fiers I would say flatly no. I'd say the same placebo that makes 'audiophiles' spend ridiculous amounts of capital on audio would be at work but this is cynical speculation at best. Then again, studies are rarely accurate anyway, especially ones done online with no criteria.

It's been my experience that most true audiophiles are more familiar with how to pull out their credit card than they are familiar with what good sound is.

Lol so true.

Personally i did an accounting sheet and charted out expenses...

well the expense sheet said to me just briefly...

if i forgo junk food for a year and plus another $300 on top i could have an LCD-2...

humm hard choices and sacrifice, oh the torture!

Quote:

Originally Posted by luisdent

Oh man, don't get me going on my sense of smell. Sometimes i wish i couldn't smell anything. It drives my wife crazy. She is very modest with scented things, but I notice every little detail. No joke, she started using listerine the other day, which is a strong scent I know, but I smelled it from the other end of the apartment (two rooms and a long hallway) and she got frustrated, because she can't so much as open a bottle of anything without me complaining "what's that smell?" haha. But it really stinks. I smell smoke anywhere and everywhere when it doesn't bother anyone else. I sometimes feel like i can't just get a break from smells. :-/ Heaven forbid the neighbors below us decide to cook their foreign wet diaper food ugh... lol

Yeah, smells etc have weird travel times,

apparently the hair folicles in the nose are so sensitive i think its either 1billionth or 1trillionth of the scent is all it takes to trigger them,

listerine is frustrating though it doesnt like going away anytime soon.

Diaper food eh?

Try indian vindaloo oh heck,

on terms of smell, using that got the quickest meeting and a sale at the end after saying would be back in at the end of the day to see how things are going.

i cant hear the 22khz until i put the volume to the max on my zero dac with my 1840s it was very faint but i could hear it , the 20 was easy but the volume was 20 % higher than my normal volume ,at normal volume it was noticable but only because my main intent was to listen to it , i would bet my entire setup that i wouldnt be able to hear it in my music if someone overlayed that track into my music hahahaha

It would be interesting to attached an age to the group of people that could hear over 20KHz. A 60 year old male with years of heavy rock listening that could hear over 20KHz could be a good subject for hearing research.

I think most people who report being able to hear above 20kHz turned the volume up to be able to do that and are either just feeling sound pressure or are hearing some sort of distortion in the audible spectrum because the spike in the inaudible spectrum is so big.

I think most people who report being able to hear above 20kHz turned the volume up to be able to do that and are either just feeling sound pressure or are hearing some sort of distortion in the audible spectrum because the spike in the inaudible spectrum is so big.

You guys must all have blown your eardrums. I can easily hear well over 20kHz . For example, I created a [.wav file] that plays a sweep from 11kHz all the way up to 44kHz and I can easily hear it the whole time.

Okay, now where is the trollface emoticon?

okay,, obviously I am being facetious. If you haven't yet figured out what I did, then you should check out the wiki article onaliasingandNyquist frequency. Because the sample rate of the wav file is 44100 Hz, the nyquist frequency is 22050Hz, which means the part of the signal above 22050Hz is aliased to a sound less than 22050Hz; hence it is audible with this sampling rate. Okay, stop flaming me now, thanks!

You guys must all have blown your eardrums. I can easily hear well over 20kHz . For example, I created a [.wav file] that plays a sweep from 11kHz all the way up to 44kHz and I can easily hear it the whole time.

Okay, now where is the trollface emoticon?

okay,, obviously I am being facetious. If you haven't yet figured out what I did, then you should check out the wiki article onaliasingandNyquist frequency. Because the sample rate of the wav file is 44100 Hz, the nyquist frequency is 22050Hz, which means the part of the signal above 22050Hz is aliased to a sound less than 22050Hz; hence it is audible with this sampling rate. Okay, stop flaming me now, thanks!

You guys must all have blown your eardrums. I can easily hear well over 20kHz . For example, I created a [.wav file] that plays a sweep from 11kHz all the way up to 44kHz and I can easily hear it the whole time.

Oh...so You're the one. Except, you're not.

The sample file sweeps from just over 20KHz downward. There's nothing in the file anywhere near to 44KHz because that's the sampling frequency, and there can be no audio above 1/2 the sampling frequency.

You can hear it the whole time because at no time does anything in that file exceed the normal range of human hearing.

I would strongly caution everyone not to try that test while increasing the play level until you think you can hear the very highest tone. It's a sweep, and does pass through the range of highest hearing sensitivity. High levels can easily cause permanent and irreversible hearing damage. Headphones are not hearing test instruments, and simply trying to see how high a frequency you can hear is very dangerous. The tendency is to go up to the point where you can't hear the tone, then increase the level until you can. You have no idea what SPL your headphones are presenting at those frequencies, and could be causing damage to your hearing as a result. High level high frequencies can cause distortions down in the audio band that you could hear, but won't represent your ability to hear real high frequencies. Just because you might be able to force enough volume into your skull to detect 22KHz doesn't mean you have usable hearing up there.

Accept the fact that you are in the range of normal, protect your hearing throughout your life by avoiding high sound levels, and leave hearing tests to the experts.

I'd like to add that just because you can hear a sound at really high volumes doesn't mean you can really "hear" that sound. If you get a high sensitivity dish microphone like the CIA probably uses, you can hear a mail truck 2 miles away. Without it you probably won't hear anything. If you have the volume at max and barely hear a high frequency tone, you probably can't hear it at regular volumes and especially not with other tones (music) getting in the way. So I would argue this test is only valid up to regular listening volumes, even if those are loud. If you can't play a song at the same volume, it's not really proving anything. While you technically can hear "some" amount of that frequency at "some" volume, in 99% of cases you wouldn't actually hear it. I think that all made sense. :-P

I confess, that I can only hear the highest tones at louder volumes. I can probably hear between 18.5-19.5khz without raising the volume louder than a loud song. And my audiologist was very impressed with my hearing tests and noted that I passed the tone tests with 100% accuracy even at the quietest volumes. He hadn't seen that before. :-P So, unfortunately, without a proper testing environment, capable equipment, etc. it's probably impossible to really know you're actual hearing limit. I would guess the average limit is around 16khz with some good ears up to 18-20khz.

I'd like to add that just because you can hear a sound at really high volumes doesn't mean you can really "hear" that sound. If you get a high sensitivity dish microphone like the CIA probably uses, you can hear a mail truck 2 miles away. Without it you probably won't hear anything. If you have the volume at max and barely hear a high frequency tone, you probably can't hear it at regular volumes and especially not with other tones (music) getting in the way. So I would argue this test is only valid up to regular listening volumes, even if those are loud. If you can't play a song at the same volume, it's not really proving anything. While you technically can hear "some" amount of that frequency at "some" volume, in 99% of cases you wouldn't actually hear it. I think that all made sense. :-P

I confess, that I can only hear the highest tones at louder volumes. I can probably hear between 18.5-19.5khz without raising the volume louder than a loud song. And my audiologist was very impressed with my hearing tests and noted that I passed the tone tests with 100% accuracy even at the quietest volumes. He hadn't seen that before. :-P So, unfortunately, without a proper testing environment, capable equipment, etc. it's probably impossible to really know you're actual hearing limit. I would guess the average limit is around 16khz with some good ears up to 18-20khz.

I used to service some ultrasonic scanning equipment and I could absolutely hear that. I have no idea what level it was but I am sure it was pretty high. We were supposed to wear hearing protectors when we were working on it. Now that I am older I am sure I couldn't hear it today though.

I used to service some ultrasonic scanning equipment and I could absolutely hear that. I have no idea what level it was but I am sure it was pretty high. We were supposed to wear hearing protectors when we were working on it. Now that I am older I am sure I couldn't hear it today though.

There are many factors in things like this. Ultrasound starts around 20khz, so it is theoretically possible to hear it with perfect hearing. However, it is more likely you were hearing one of a number of other things. Power transformers can cause high pitched whines or tones. Very high pitched. There could also be other electronic components that made the sound. Very high pitched sounds "sound" higher when they aren't accompanied by lower frequencies. In other words, a series of simultaneous tones from say 15khz-19khz will sound lower than a pure 19khz tone due to masking and combining of frequencies. So a single 17khz tone can even "sound" extremely high pitched. They actually use this tone to scare off teenagers in some countries where older people live, because the older people can't hear it but it annoys the teenagers (no joke).

Lastly, you could have simply been hearing the 20khz frequency it emitted, especially if it emitted it at a loud volume, hence the need for hearing protection they had. Can't say for sure, but it is possible to hear to 20hz. It is scientifically tested and proven. It's just that it takes perfectly health hearing to do so. In this day and age that is becoming far less common. :-/